The present invention is concerned generally with article handling systems and in particular with a novel and improved discharge apparatus for an article handling system.
While the invention may find utility in other applications, the invention will be particularly described herein with reference to an article handling system of the type illustrated and described in U.S. Pat. No. 4,979,870 entitled "AUTOMATIC TRAY LOADING, UNLOADING AND STORAGE SYSTEM" which patent is commonly owned herewith. This patent illustrates and describes a system for loading articles such as can ends which are supplied from a first location in a facewise nested condition into trays and thereafter unloading these articles from the trays for transport to a second location. This system is designed to compensate for differences in the rate at which articles are supplied from the first location and the rate of demand for the articles at the second location, such that previously stored articles may be removed from one or more trays to make up for an increase in the demand or decrease in the supply, and on the other hand articles may be stored in trays to compensate for either a decrease in the demand or an increase in the supply.
The present invention will be illustrated and described with particular reference to the problem of handling can ends or similar facewise nested articles in such a system. In the manufacture of containers such as beverage cans or the like, a great number of can ends are required. Generally speaking, container bodies require but a single end closure piece. Moreover, in many applications the so-called "flip-top" or "pop-top" containers are utilized, which requires that the can end be fabricated with suitable prescorings and pull rings to define tear-away openings.
Thus while the can ends are generally nestable in a generally flat coaxial facewise arrangement, the tabs or rings may tend to cause the can ends to push apart and tilt somewhat out of the desired coaxial position. It is therefore important that handling apparatus and methods take account of this tendency, and provide sufficient axial support to overcome it.
In commercial scale operations, many thousands of such can ends must be handled and preferably automatically fed or delivered between various points in either end fabrication operations or in packaging operations wherein they are assembled with filled containers. It has heretofore become the practice to handle can ends in individual groups of a preselected length, which thereby also contain a reasonably accurate and predictable count of can ends or like articles. In the fabrication operation, it is necessary to deliver the ends from an initial press which forms the ends to subsequent stations wherein the pull tabs and scoring are applied, various coatings, etc. are applied, and the like to produce the finished end. Finally the ends are separated into groups of predetermined lengths, generally referred to as "sticks" in the art, and these sticks are often packaged in kraft paper bags for subsequent storage or transport.
In the system of the above-referenced U.S. Pat. No. 4,979,870, the loading, unloading and storage system or compensating system is generally placed between operations in the can end fabrication process. In such a process, the ends are generally fed in a continuous flow over suitable infeed/outfeed lanes from one station to the next. In order to handle the cans in the system of the above-mentioned patent, it is necessary that the incoming continuous flow be initially separated into individual groups for handling and placement with respect to the trays. By the same token, it is necessary upon removal of ends from the trays for delivery, in accordance with demand, to downstream fabricating operations, that the individual groups or sticks of ends be again fed into suitable lanes in a continuous flow.
The present invention provides a novel and improved discharge apparatus for delivering individual groups of ends to an outfeed area and, in so doing to reunite the individual groups of ends to form a continuous flow of articles as they enter an outfeed lane.